A developer tests both claude-3-5-haiku-20241022 and claude-3-5-sonnet-20241022 on a task that requires interpreting a 150,000-token codebase and identifying security vulnerabilities. Claude 3.5 Haiku returns results in 4 seconds; Claude 3.5 Sonnet takes 22 seconds. Both have 200K context windows. A stakeholder argues for Haiku to reduce latency. What is the architect's most important counter-consideration?

C is correct because the latency advantage of Haiku is not free — at the frontier of its capability (complex multi-file security analysis at 150K tokens), its reasoning quality is lower than Sonnet's. In security applications, a missed vulnerability (false negative) is a more serious failure than a slow scan. The architect must surface this quality-latency tradeoff explicitly rather than allowing a latency optimization to silently reduce security coverage. A is wrong because while output token limits differ between models, 4,096 output tokens is sufficient for most vulnerability reports; this is a secondary concern compared to analysis quality. B is wrong because the per-call cost difference between Haiku and Sonnet does not converge at high input token counts — they have distinct input pricing regardless of token volume; this claim is factually incorrect. D is wrong because Claude 3.5 Haiku does support tool use; it is a capable model for tool-calling workflows.